The present invention relates to a method of detecting of hydrocarbon deposits.
Methods of detecting hydrocarbons are known. One of such methods which is based on the use of a transient electromagnetic field is disclosed in A. Hordt, P. Andrieux, F. M. Neubauer, H. Ruter, and K. Vozoff, 2000, A first attempt at monitoring underground gas storage by means of time-lapse multichannel transient electromagnetics: Geophysical Prospecting, 48, 489-509.
In accordance with this method a pulse electromagnetic field is excited on the earth surface and penetrates into the earth reaching great depths. The transient electromagnetic process which is registered on the surface reflects an inner structure of the radiating object. However, the detection of productive deposits of hydrocarbons in this method is not sufficiently reliable, since the physical nature of the transient electromagnetic process is not specific during location of high-ohmic collectors. The application of this method for many years showed its low efficiency for detection of deposits of oil and gas. Another method of detection of hydrocarbons based on a seismo electric effect is disclosed in U.S. Pat. No. 4,904,942 to Thompson. In accordance with this method a seismic pulse is excited on the earth surface so that a seismic wave crosses the depths with investigating object and an electromagnetic field resulting from a seismo electric effect in the investigated object reaches the earth surface and measures as an integrator of the presence of this object.
Other investigators of the seismo electric method for detection of oil and gas use the same concept as Thompson. Experiments conducted in this way and disclosed in the publication A. H. Thompson and G. A. Gist, 1993, Geophysical applications of electrokinetic conversion: The Leading Edge, 12, No. 12, 1169-1173. M. W. Haartsen, and R. P. Pride, 1997, Electroseismic waves from point sources in layered media: Journal of Geophysical Research, Vol. 102, No. B11 24745-24769; S. Garambois and M. Dietrich, 2001, Seismoelectric wave conversions in porous media; Field measurements and transfer function analysis: Geophysics Vol. 66, No3, 1417-1430 showed that the reached depths of investigation with this method does not increase 300 m. Therefore the above mentioned methods have very little practical value or no value at all.
Because of low efficiency of the data obtained during detecting of deposits of hydrocarbons with the existing geophysical methods, the seismic method, the coefficient of success of drilling does not exceed 10%.